Selective photocatalytic carbon dioxide conversion with Pt@Ag-TiO 2 nanoparticles

Abstract Pt@Ag-TiO 2 nanocomposites were prepared and tested for photocatalytic CO 2 conversion in the presence of H 2 O. The characterizations showed that Pt@Ag core@shell structures were formed. The photocatalytic activity of Pt@Ag x -TiO 2 catalysts with different Ag content showed that the deposition of Ag shell could increase the photocatalytic CO 2 reduction efficiency and selectivity by suppressing H 2 generation. Pt@Ag 1.0 -TiO 2 with an Ag content of 1.95 wt.‰ showed a maximum CH 4 formation rate of 160.3 μmol·g −1 ·h −1 , together with a CO 2 reduction selectivity of 87.90%. PL spectra and photocurrent measurements indicated that Pt@Ag 1.0 -TiO 2 had the highest photogenerated electron-hole separation efficiency among all the prepared photocatalysts.